The scientists have claimed to have experimentally demonstrated, for the first time, the ability to electrically generate and control valley electrons in a two-dimensional semiconductor (TMDC). This is an especially important advance because TMDCs are considered to be more ‘device ready’ than other semiconductors that exhibit valleytronic properties.
Xiang Zhang, director of Berkeley Lab's Materials Sciences Division, said: "This is the first demonstration of electrical excitation and control of valley electrons, which will accelerate the next generation of electronics and information technology."
The team’s research could lead to a new type of electronics that utilises all three degrees of freedom--charge, spin, and valley, which together could encode an electron with eight bits of information instead of two. This means future computer chips could process more information with less power, enabling faster and more energy efficient computing technologies.
"Our research solved two main challenges in valleytronic devices. The first is electrically restricting electrons to one momentum valley. The second is detecting the resulting valley-polarised current by circular polarised electroluminescence," explained Yu Ye, a researcher in Zhang’s lab. "Our direct electrical generation and control of valley charge carriers, in TMDC, opens up new dimensions in utilising both the spin and valley degrees of freedom for next-generation electronics and computing."
